I accidentally deleted the caveGRoomDoor02 from the object list as I was going back and forth from previewing objects and looking at them in the rendor window.

If I double click Skyrim, update and myMod then click details then click the deleted column I get 5 items with a D in that column.

4 say REFR D (0001B1AE)

1 says STAT D and nothing else.

I assume the STAT is my deleted object and the other 4 are references of it?

How do I undelete them?

i would use TESVEdit and just delete it.

or could find the info and just re-add it to your mod.